letter shell 2适配

Name		Name	Last commit message	Last commit date
Latest commit History 1 Commit
GD32F4xx_Firmware_Library_V2.1.3/GD32F4xx_Firmware_Library_V2.1.3		GD32F4xx_Firmware_Library_V2.1.3/GD32F4xx_Firmware_Library_V2.1.3
README.en.md		README.en.md
README.md		README.md
letter-shell.rar		letter-shell.rar
teraterm-4.95.zip		teraterm-4.95.zip

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